A study of the relationship of nightmares (disturbing dreams that awaken the sleeper ) and bad dreams (disturbing dreams that do not awaken the sleeper) to well-being found the frequency of nightmares was inversely correlated with well-being, a correlation that was greater than that between bad dreams and well-being. The study used dream logs (as opposed to retrospective report) and this methodology resulted in a much greater reported frequency of nightmares and bad dreams in the studied population. Ss were college students.

The authors conclude that "..the data indicate that people who experience bad dreams are low on self-reported measures of well-being, but not to the extent exhibited by those with nightmares. These results form a pattern that suggests that scores on measures of well-being are inversely related to the position of a dreaming experience on the dimension of negative dream affect." They also indicate that studying nightmare distress may be an even more productive avenue of investigation.

Nightmares and bad dreams: Their prevalence and relationship to well-being.

By Zadra, Antonio; Donderi, D. C.
Journal of Abnormal Psychology. 2000 May Vol 109(2) 273-281